Display device and head-mounted display

Abstract

A display device includes a display panel having a display surface and a lighting device that supplies light to the display panel. The lighting device includes a light source, and an optical member having at least a light exit surface through which the light emitted by the light source exits toward the display surface of the display panel. The optical member includes a light refraction portion that imparts an anisotropic refraction effect to at least light rays exiting through an edge section of the light exit surface to be oriented toward a center side of the display surface. The display device further includes a low refraction index layer interposed between the display panel and the optical member, and the low refraction index layer has a refraction index lower than at least a refraction index of the optical member.

The invention claimed is: 
     
       1. A display device comprising:
 a display panel having a display surface that displays an image; and 
 a lighting device that supplies light to the display panel, wherein 
 the lighting device includes a light source, and an optical member having at least a light exit surface through which the light emitted by the light source exits toward the display surface of the display panel, 
 the optical member includes a light refraction portion that imparts an anisotropic refraction effect to at least light rays exiting through an edge section of the light exit surface to be oriented toward a center side of the display surface, 
 
       the display device further comprises a low refraction index layer interposed between the display panel and the optical member, the low refraction index layer having a refraction index lower than at least a refraction index of the optical member,
 the light refraction portion is formed by a Fresnel lens arranged on a light incident surface of the optical member, and 
 the Fresnel lens has a curvature relatively larger at an outer peripheral end side of the light exit surface than at a central side of the light exit surface. 
 
     
     
       2. The display device according to  claim 1 , further comprising a light guide plate including a light incident end surface that is a part of an outer peripheral end surface of the light guide plate and through which the light emitted by the light source enters, and a light exit plate surface that is one of a pair of plate surfaces of the light guide plate and through which the light exits, the light guide plate being arranged to be overlapped with the optical member and arranged at a side opposite to a side of the display panel, wherein
 the optical member includes a light incident surface facing the light exit plate surface of the light guide plate, and the light refraction portion is arranged on the light incident surface, 
 the light refraction portion includes prisms each of which extends along an orthogonal direction orthogonal to a normal direction of the light incident end surface and has an apex part and a pair of inclined surfaces interposing the apex part, the prisms being aligned along the normal direction, and 
 the prisms include at least an apex part eccentric prism arranged at an end side of the light incident surface in the normal direction, the apex part eccentric prism having the apex part eccentric to be close to an end of the light incident surface in the normal direction. 
 
     
     
       3. The display device according to  claim 1 , further comprising:
 a light guide plate including the light incident end surface and a light exit plate surface, the light incident surface being at least a part of an outer peripheral end surface of the light guide plate and through which the light emitted by the light source enters, and the light exit plate surface being one of a pair of plate surfaces of the light guide plate and through which the light exits, the light guide plate being arranged to be overlapped with the optical member, and 
 an anisotropic light condensing member interposed between the light guide plate and the optical member, wherein 
 the anisotropic light condensing member includes an anisotropic light condensing layer that imparts an anisotropic light condensing effect to light such that a light condensing degree in the normal direction of the light incident end surface is made larger and a light condensing degree in an orthogonal direction orthogonal to the normal direction is made smaller. 
 
     
     
       4. The display device according to  claim 3 , further comprising a diffusion member interposed between the display panel and the low refraction index layer to diffuse the light exiting through the light exit surface of the optical member, wherein
 the diffusion member includes an anisotropic diffusion layer that imparts an anisotropic diffusion effect to the light such that a light diffusion degree in the normal direction is made smaller and a light diffusion degree in the orthogonal direction is made larger. 
 
     
     
       5. The display device according to  claim 1 , further comprising a diffusion member interposed between the display panel and the low refraction index layer to diffuse the light emitted from the light exit surface of the optical member. 
     
     
       6. The display device according to  claim 5 , wherein the diffusion member includes at least a diffusion layer that diffuses light and a polarizing reflection layer that polarizes and reflects light. 
     
     
       7. The display device according to  claim 1 , further comprising a support member that supports at least the display panel from a side of the optical member. 
     
     
       8. The display device according to  claim 1 , wherein the low refraction index layer is a resin layer formed of a synthetic resin material. 
     
     
       9. A display device comprising:
 a display panel having a display surface that displays an image; 
 a lighting device that supplies light to the display panel; and 
 a light guide plate; 
 wherein the lighting device includes a light source, and an optical member having at least a light exit surface through which the light emitted by the light source exits toward the display surface of the display panel, 
 the optical member includes a light refraction portion that imparts an anisotropic refraction effect to at least light rays exiting through an edge section of the light exit surface to be oriented toward a center side of the display surface, 
 the display device further comprises a low refraction index layer interposed between the display panel and the optical member, the low refraction index layer having a refraction index lower than at least a refraction index of the optical member, 
 the light guide plate includes a light incident end surface that is a part of an outer peripheral end surface of the light guide plate and through which the light emitted by the light source enters, and a light exit plate surface that is one of a pair of plate surfaces of the light guide plate and through which the light exits, the light guide plate being arranged to be overlapped with the optical member and arranged at a side opposite to a side of the display panel, wherein 
 the optical member includes a light incident surface facing the light exit plate surface of the light guide plate, and the light refraction portion is arranged on the light incident surface, 
 the light refraction portion includes prisms each of which extends along an orthogonal direction orthogonal to a normal direction of the light incident end surface and has an apex part and a pair of inclined surfaces interposing the apex part, the prisms being aligned along the normal direction, and 
 the prisms include at least an apex part eccentric prism arranged at an end side of the light incident surface in the normal direction, the apex part eccentric prism having the apex part eccentric to be close to an end of the light incident surface in the normal direction. 
 
     
     
       10. The display device according to  claim 9 , further comprising:
 a light guide plate including the light incident end surface and a light exit plate surface, the light incident surface being at least a part of an outer peripheral end surface of the light guide plate and through which the light emitted by the light source enters, and the light exit plate surface being one of a pair of plate surfaces of the light guide plate and through which the light exits, the light guide plate being arranged to be overlapped with the optical member, and 
 an anisotropic light condensing member interposed between the light guide plate and the optical member, wherein 
 the anisotropic light condensing member includes an anisotropic light condensing layer that imparts an anisotropic light condensing effect to light such that a light condensing degree in the normal direction of the light incident end surface is made larger and a light condensing degree in an orthogonal direction orthogonal to the normal direction is made smaller. 
 
     
     
       11. The display device according to  claim 10 , further comprising a diffusion member interposed between the display panel and the low refraction index layer to diffuse the light exiting through the light exit surface of the optical member, wherein
 the diffusion member includes an anisotropic diffusion layer that imparts an anisotropic diffusion effect to the light such that a light diffusion degree in the normal direction is made smaller and a light diffusion degree in the orthogonal direction is made larger. 
 
     
     
       12. The display device according to  claim 9 , further comprising a diffusion member interposed between the display panel and the low refraction index layer to diffuse the light emitted from the light exit surface of the optical member. 
     
     
       13. The display device according to  claim 12 , wherein the diffusion member includes at least a diffusion layer that diffuses light and a polarizing reflection layer that polarizes and reflects light. 
     
     
       14. The display device according to  claim 9 , further comprising a support member that supports at least the display panel from a side of the optical member. 
     
     
       15. The display device according to  claim 9 , wherein the low refraction index layer is a resin layer formed of a synthetic resin material. 
     
     
       16. A display device comprising:
 a display panel having a display surface that displays an image; 
 a lighting device that supplies light to the display panel; and 
 a light guide plate, 
 wherein the lighting device includes a light source, and an optical member having at least a light exit surface through which the light emitted by the light source exits toward the display surface of the display panel, 
 the optical member includes a light refraction portion that imparts an anisotropic refraction effect to at least light rays exiting through an edge section of the light exit surface to be oriented toward a center side of the display surface, 
 the display device further comprises a low refraction index layer interposed between the display panel and the optical member, the low refraction index layer having a refraction index lower than at least a refraction index of the optical member, 
 the light guide plate includes a light incident end surface and a light exit plate surface, the light incident surface being at least a part of an outer peripheral end surface of the light guide plate and through which the light emitted by the light source enters, and the light exit plate surface being one of a pair of plate surfaces of the light guide plate and through which the light exits, the light guide plate being arranged to be overlapped with the optical member, and 
 an anisotropic light condensing member interposed between the light guide plate and the optical member, wherein 
 the anisotropic light condensing member includes an anisotropic light condensing layer that imparts an anisotropic light condensing effect to light such that a light condensing degree in the normal direction of the light incident end surface is made larger and a light condensing degree in an orthogonal direction orthogonal to the normal direction is made smaller. 
 
     
     
       17. The display device according to  claim 16 , further comprising a diffusion member interposed between the display panel and the low refraction index layer to diffuse the light exiting through the light exit surface of the optical member, wherein
 the diffusion member includes an anisotropic diffusion layer that imparts an anisotropic diffusion effect to the light such that a light diffusion degree in the normal direction is made smaller and a light diffusion degree in the orthogonal direction is made larger. 
 
     
     
       18. The display device according to  claim 16 , further comprising a diffusion member interposed between the display panel and the low refraction index layer to diffuse the light emitted from the light exit surface of the optical member. 
     
     
       19. The display device according to  claim 18 , wherein the diffusion member includes at least a diffusion layer that diffuses light and a polarizing reflection layer that polarizes and reflects light. 
     
     
       20. The display device according to  claim 16 , further comprising a support member that supports at least the display panel from a side of the optical member. 
     
     
       21. The display device according to  claim 16 , wherein the low refraction index layer is a resin layer formed of a synthetic resin material.